Cork.



. I .or exposed to acid-vapors instead of formic "UNIT D STA ES-Patented July as, 1903.

F FFlQE.

CORK..-

srscmrcnmon formingpart of letters Patent No. 734,551, dated July as,1903.

Application filed May 10,1902. Serial No. 106,816. (No sp cimens.)

a all it may concern.-

' ,BeitknownthatL'HEINRICHHELBrNo,con-- 'sulti-n'gchemist, of 63 QueenVictoria street,

London, England, have invented certain new 5 and useful Improvements inCorks, of which the following is a specification.

' This invention relates toimprovements'in corks. r

It iswell known that wine and other pota cork stoppers frequently-exerta gradual dis- -solvent or deteriorating efiect upon the cork, wherebythe cork itself becomes softened and rotten or the liquidacqnires acorky taste or sometimes a bad color, It has been attempted to remedythese defects by coating the surface of the cork with paraffin or withsolutions of caoutchouc, nitrocellulose, or the; like; but it has beenfound that the employ- 2o ment of these protective layers is in practiceaccompanied by serious disadvantages.

I have now discovered that the endurance and im permeability of the corkmay be greatly increased without material loss of elasticity byimpregnating the cork with casein or other albumen capable offorming'soluble salts with alkalies and fixing the albumen preferablywith formic aldehyde. The corks may, however, after impregnation withthe soluble-albumen salt be dipped in a dilute acid-bath aldehyde. Thesoluble casein salts have the peculiar property of easily penetratingthe cork tissues even when employed in concentrated solutions and can beprecipitated in the tissues by the natural acidity of the wine. Inpra-ctice, however, it is found more advantageousto'fix the casein inthe impregnated corks before-use by treatm'ent'with dilute 01- formicaldehyde. The casein thus fixed forms insoluble elastic and invisiblefilms in the cork tissue which resist the penetration of liquids. 1

In ,order to carry out my invention, I cm; ploy, preferably, a neutralaqueous solution of the sodium salt of casein. For example,

' I dip the'corks in a bath made by dissolving onehundred parts ofcasein in one thousand ble liquids stored in bottles and the like withgame or mineral acids or preferably with parts of water with the aid ofsufficient caustic soda to produce a neutral solution. The

allowed to remain inthe bath for one or more hours or until cold. Theyare then drained and dried or dipped direct into a second bathcontaining a five-per-cen't. solution of formic for one hour and againdrained and dried. The'order of these baths may be reversed, or in theplace of a formic aldehyde solution 'I may expose the corks to formicaldehyde gas.

I do not limit myself to baths of the above strength, and thetemperature and time of exposure may, of course, alsojbe varied withindipping is preferably carried out at atemperature of centigrade, and thecorksare.

aldehyde, also preferably at 50 centigrade,

ing in soaking the cork in an aqueous solution of a soluble casein saltfixing with formic aldehyde and drying.

. '5. Method of treating cork stoppers consisting in soaking the cork inan aqueous solution of an alkali salt of casein fixing with formicaldehyde and drying.

6. Method of treating cork stoppers consisting in soaking the cork in anaqueous solu- .tion of a sodium salt of casein fixing with formicaldehyde and drying.

7. Asanewarticle of manufacturea caseinated cork stopper.

in witness whereof I have hereunto signed .my name in the presence oftwo subscribing witnesses. v HEINRICH HEL'BING.

Witnesses: I

GE GE BELOE E LIs, ROBERT MILTON SREA roIN'r.

